In the 1880's, an Academy Standard film format was created, wherein the film stock had two rows of sprocket holes, or film perforations, each film frame had an aspect ratio (width divided by height) of 1.37:1, and the film frames were spaced apart by four perforations (0.748 inch). This format was widely adopted in the 1920's. In the 1950's, a new projection aspect ratio called Wide Screen Academy Format was adopted, wherein the same film was used, but the aperture of the projector film gate was changed so the projected image had a smaller length, or height, than previously, for an aspect ratio of 1.85:1. It was thought that the wider format would differentiate the motion picture images from television images. However, the film frames were still of the same size and still spaced apart by four perforations, with the top and bottom of each frame cropped to produce an aspect ratio of 1.85. As a result, the gap or space between the projected areas of adjacent film frame occupied about 40% of the length of the film stock. The film titles were centered on the film frames, to aid the projectionist to adjust the framing knob so the center of the film frames lay at the center of the projection aperture of the film gate mask.
It would appear that the reason why the Wide Screen Academy Format was readily accepted by theater owners was that about the only change to the projector was to install a new film gate mask and to replace the lens. This current format has been in use up to the present, for more than 90% of all release prints. A small number of release prints are in the Cinemascope format, wherein the same film stock is used, but the film frames have a greater width.
There have been suggestions for minimizing the amount of film used. For example, U.S. Pat. Nos. Butler 3,565,521 and Cole 3,583,803 suggest the use of projection apertures (of the film gate mask) of smaller heights and different aspect ratios to save the amount of film used when standard 35 mm film stock is used. However, because of competition from television and aversion to any change that would degrade the motion picture image, there is reluctance to accept a smaller projection aperture size.
Lente U.S. Pat. No. 3,865,738 suggests the use of the current projection aperture, with film frames of smaller height and spaced apart by only three sprocket holes to minimize wastage. Although this would result in reducing film "wastage" from about 40% to 20%, this format has not been adopted. A new film format that used current 35 mm film stock and the current projection aperture size, and which virtually eliminated film "wastage", while facilitating conversion of projectors to the new format, would be more readily accepted by the motion picture film industry.